Head-stock for machine tools



. W. BATH HEAD STOCK FOR MACHINE TOOLS 5 SheetsmSheet Filed July 17, y1931 @mmf 12% c@ ,ff

@shaw f Dec. 20, s' W. BATH HEAD STOCK AFOR MACHINE TOOLS 5 Sheets-Sheet 2 Filed 4July 17, 1931 www@ ei, 2Q, 1932. s W, @ATH LSQL `HEAD* STOCK FOR MACHINE TGDLS Filed July 17, 1931 5V sneetsnsneet 5 Patented Dec. 20, 1932 UNiTsn STATES Parent orales STANLEY W. BATH, OF SHREWSBUBY, BASSACHUSETTS, ASSEGNOR TO JOHN BATH, OF VJORCESTER, MASSACHUSETTS HEAD-STOCK FOR ltACI-INE TOOLS Application filed July 17, 1931. Serial No. 551,539.

This invention relates to a head-stock for a machine tool, such as a grinding machine or lathe, in which hydraulic or pneumatic mechanism is provided for moving the work center toward or away from the work.

It is the general obj ect of my invention to provide an improved device for limiting the movement of withdrawal of the work center and its support.

A. further object is to provide improved means for ej ecting the work center from its support, when such removal is desired. Other features of the invention relates to an improved construction of head-stock frame and slide, by which transverse adjustment of the work center is facilitated.

My invention further relates to arrangements and combinations of parts which will be hereinafter described and more particularly pointed out in the appended claims.

A preferred form of the invention is shown in the drawings, in which Fig. l is a plan view of portions of a duplex grinding machine;

Fig. 2 is an end elevation of one of the head-stocks, looking in the direction of the arrow 2 in Fig. 1;

Fig. 3 is a sectional front elevation of the head-stock, ltaken along the line 3-3 in Fig. 2;

Fig. 4 is an end elevation of the head-stock slide;

Fig. 5 is a partial front elevation of the slide, looking in the direction of the arrow 5 in Fig. 4;

Fig. 6 is a partial plan View of the slide, looking in the direction of the arrow 6 in Fig. 5;

Fig. 7 is a detail sectional elevation of certain adjusting mechanism to be described;

Fig. 8 is an end elevation of the lower or body portion of the head-stock;

Fig. 9 is a partial front elevation thereof, looking in the direction of the arrow 9 in Fig. 8;

Fig. 10 is a partial end elevation of the upper or cap portion of thehead-stock;

Fig. 11 is a detail sectional elevation, taken along the line 11-11 in Fig. 3;

Fig. 12 is a detail sectional view, takenl along the line 12--12 in Fig. 3, and

Fig. 13 is a view similar to Fig. 12 but showing the parts in a` different position.

Referring to Fig. l, l have shown my invention embodied in a duplex grinding machine in which two pieces of work W and WV are supported upon head centers 20 and 21 and tail centers 22 and 23. A single grinding wheel G may be used for Urindingboth pieces of work V27 and W alternately.

The tail centers 22 and 23 are secured in a tail-stock 25, which may be clamped or otherwise secured to the table 26 (Fig. 2) of the grinding machine. A head-stock H is provided for the head center 20 and a headstock H for the head center 21. These headstocks are duplicates and a description of the head-stock H will apply equally to the headstock H.

The head-stock H comprises a slide 30 (Fig. 4), and a head-stock frame formed of a body portion 31 (Fig. 8) and an upper or cap p0rtion 32 (Figs. 2 and 10). The slide 30 (F igs. 2 and 4) is provided with bearing portions 34 and 35 and with a depending front liange 36.

The bearing portions 34 and 35 engage corresponding bearing portions on the table 26, the portion 34 being substantially horizontal and the portion 35 being substantially inclined when the head-stock is in operative position.

The flange 36 engages the front edge of the table 26 and limits rearward and downward movement of the slide 30. A hook bolt 37 is mounted in an inclined opening 38 of the slide 30 and the lower or hook end of the bolt 37 .is positioned in a recess 39 in the inclined face of the table 26.

`When the bolt 37 is drawn upward by a clamping nut 40, the hook engages the upper side wall 41 of the recess 39 and securely clamps the slide 30 in axially adjusted position. Then the nut 40 is loosened, the headstock may be easily moved along its guideways on the table 26. I

rlhe head-stock body portion 31 (Fig. 8) lis provided with horizontal bearing portions 44 and 45, adapted to rest on corresponding A bearing'portions 46 and 47 (Fig. 4) formed on the slide 30. Adjusting screws 48 and 49 are provided for moving the head-stock for Ward or rearward transversely to its axis and relatively to the slide 30.

The adjusting screws 48 and 49 engage hardened steel studs 50 (Fig. 7) mounted in recesses 51 (Fig. 4) in the slide 30. By loosening one of the screws 48 orl 49 and tightening the other screw, the head-stock may be adjusted transversely as desired.

A clamping screw 52 extends loosely downward through a slot 53 (Fig. 8) in the body 31 and is screwed into a threaded opening 54 (Fig. 4) in the slide 30. The screw 52 is provided with a handle 55 at its upper end, and the hub portion of the handle engages the upper surface of the body 31 when the screw is tightened, firmly clamping the body against the slide 30. The body 31 is provided with ribs or projections 57 and 58 (Figs. 8 and 9) iitting corresponding transverse guideways 60 (Fig. 6) in the slide 30 and is thus held in correct alignment.

The cap 32 is secured to the head-stock body 31 by clamping bolts 62 (Figs. 2 and 8), and the cap and body are provided with bearing surfaces 63, collectively forming a rectangular guideway for a bushing or quill 65 having a tapered axial opening 66 in which the head center 20 is seated.

, The right hand end of the quill 65, as viewed in Fig. 3, has a reduced cylindrical eX- tension 68 and a threaded end portion 69. The inner race of a ball bearing B is mounted on the projection 68 and is secured in position thereon by a clamping nut 70. The outer race of the ball bearing B supports a faceplate 7 2 (Fig. 3) in which a driving stud 73 may be mounted. The stud 73 engages a dog 74 on the work W, by which engagement the Work is rotated.

An external gear 75 (Fig. 3) is formed on the inner end portion of the face-plate 7 2 and is engaged by a pinion 76 on a drive shaft 77, suitably supported in bearings 78 in the upper part of the head-stock cap portion 32. The shaft 77 may be rotated in any convenient manner, as by a belt 79 on a pulley 80.

. It will be noted that the face of the pinion 76 is wide enough to maintain effective engagement with the gear 75 and at the same time permit substantial axial movement of the gear 75. A suitable gear cover 81 is provided for the gear 75 and pinion 76.

A cylindrical opening 85 (Fig. 3) is formed in thequill 65 to receive a piston 86 and a cup washer 87, secured in operative position on a piston rod 88 by a clamping nut 89. rllhe nut 89 clamps the pistonv 86, packing 87 and a washer 91 against a shoulder 92 on the piston rod 88. The piston rod 88 extends out through a stuffing box 93 in the head 94 of the quill 65 and also extends loosely through a bearing in a bracket 95, fixed to the headstock body 31.

The piston rod 88 is held from axial movement in its bearing by a flange 96 on the piston rod which engages one end of the bearing, and by an adjusting arm 97. The arm 97 is clamped against a shoulder on the piston rod 88 by a nut 98 and engages the opposite side of the bearing on the bracket 95.

The arm 97 is keyed to the piston rod 88 and is provided with a handle 100 and with spaced shoulders or projections 101, adapted to engage a stop pin 102 in the bracket 95. Angular movement of the piston rod 88 and arm 97 is thus limited by the shoulders 101.

The arm 97 is also provide with two recesses 103, adapted to receive a spring-pressed ball 104 mounted in a recess 105 in the bracket 95. The ball 104 thus holds the handle 100 and arm 97 yieldingly in one or the other of its operative positions.

A stop member (Fig. 3) is fixed to the inner end of the piston rod 88 and is provided with a rib or projection 111, extending transversely across the inner end of the member 110.

A stop collar 114 (Fig. 3) is mounted in the inner end of the cylindrical opening 85 in the quill 65, in position for engagement by the stop member 110.

The collar 114 is provided with a transverse groove 115 adapted to receive the rib or projection 111 when aligned therewith. A spring 117 in the cylindrical opening 85 engages the piston 86 at one end and the stop collar 114 at the other end and thus forces the quill 65 and center 20 yieldingly toward the work 1V.

A passage 120 (Fig. 3) is formed in the head 94 of the quill 65 and a iiexible tube 122 forms a hydraulic or pneumatic connection to the passage 120 and cylinder 85.

Having described the details of construction of my improved head-stock, the method of operation and advantages thereof are as follows:

During normal operation, the quill 65 and head center 20 are forced to the right (Fig. 3) until the center 20 engages the work W and presses it lirmly against the dead center A22.

This movement to the right is effected by the v action of the spring 117.

Vhen it is desired to withdraw the head center20 from the work WV, iuid pressure is applied through the pipe 122 against the xed piston 86, thus causing the quill 65 to be withdrawn, (moving to the left in Fig.

The normal angular position of the stop member 110 is as indicated in Figs. 3 and 12, with the rib or projection 111 out of alignment with the recess 115. The quill 65 is thus normally moved to the left until the stop collar 114 engages the end of the projection 111, which limits the withdrawal of the quill 65 and head center 20.

During ordinary operation, therefore, it is merely necessary to admit fluid under pressure through the pipe 122 in order to withdraw the centerl 20, and to release the Huid pressure to permit the spring 117 to advance the center 2O to engage the Work. I, however, it is desired to remove the center 2() from the quill 65, this is accomplished by turning the handle 100, moving the piston rod 88 to its second operative position (Fig. 13), in which position the projection 111 is aligned with the recess 115.

It fluid under pressure is then admitted to the cylinder 85, causing the quill to move to the left, the rib 111 will enter the recess 115 and will engage the end of the center 20, and continued pressure of the fluid will cause the center to be automatically ejected.

I am thus able to quickly and easily remove the head center from its tapered bearing in the quill 65, an operation which would otherwise be diicult to perform, as the quill-actuating mechanism makes it impossible to use the usual driving rod for ej ecting the center.

Having thus described my invention and the advantages thereof, I do not wish to be limited to the details herein disclosed, otherwise than as set forth in the claims, but what I claim is 1. In a head-stock, a head-stock frame, a work center, a support for said center mounted for sliding movement in said frame, a spring to move said support and center toward the work, fluid-operated means to move said support and center away from the work, and a device effective in one position to limit movement of said support and center away from the work and effective in another position to ej ect said center from said support.

2. In a head-stock, a head-stock frame, a work center, a support for said center mounted for sliding movement in said frame, a spring to move said support and center toward the work, fluid-operated means to move said support and center away from the work, a device eective in one position to limit movement of said support and center away Jfrom the work and effective in another position to eject said center from said support, and means to selectively position said device.

3. In a head-stock, a head-stock frame, a work center, a support for said center mounted Jfor sliding movement in said frame, a spring to move said support and center toward the work, fluid-operated means to move f said support and center away from the work,

and a device effective in one position to engage said support and limit withdrawal thereof and in another position to engage and eject said center.

41. In a head-stock` a head-stock frame, a work center, a support for said center mounted for sliding movement in said fra-me, a spring to move said support and center toward the work, fluid-operated means to move said support and center away from the work,

and a device'ez'ective in one position to engage said support and limit withdrawal thereof and in another position to engage and eject said center, saidsupport having a slotted stop collar engaged by a projecting portion of said device when said device is in one position, and receiving said projecting portion in the slot ofl said collar whensaid device is in a dii'erent position, said support in the latter case having increased travel during. which said device engages and ej ects said center.

5. In a head-stock, a head-stock frame, a Work center, a support for said center mounted for sliding movement in said frame, a spring to move said support and center t0- ward the work, fluid-operated means to move said support and center away from the work, a device to limit the withdrawal movement of said support and center, and means to position said device to limit withdrawal movement of said center only.

. 6. In a machine tool, a table, and a headstock comprising a slide, a body portion guided for transverse movement on said slide, and a cap portion secured to said body portion.

7. In a machine tool, a table, a. head-stock comprising a slide, a body portion guided for transverse movement on said slide, and a cap portion secured to said body portion, said body and cap portions having guiding surfaces collectively forming a rectangular guidevvay, and a head center support slidable therein.

8. In a machine tool, a table, a head-stock comprising a slide, a body portion guided for transverse movement on said slide, and a cap portion secured to said body portion, means to secure said cap portion to said body portion, means to secure said body portion to said slide, and means to secure said slide to said table.

9. In a machine tool, a head-stock comprising a frame, a head center, a support for said center slidable but non-rotatable in said frame, a face plate mounted to slide with said support and to rotate about the axis of the head center, and means to drive said face plate.

10. In a machine tool, a work center and a movable support therefor, fluid-operated means to withdraw said support and center from the work, and a combined stopping and ejecting device having two manually selective operative positions, said device in one position constituting a stop to limit withdrawal movement of said support and center, and said device having a portion effective in a second position of said device to engage and eject said center from said support as said W support is withdrawn.

11. In a head-stock, a head-stock frame` a work center, a support for said center mounted for sliding movement in said frame, a

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spring to move said support and center toe ward thework, Huid-operated means to move said support and center away from the Work, and means to engage said support and limit the withdrawal movement of said support and center at a predetermined point, said limiting means being manually adjustable to n position in which said means engages and @jects said center from said support during increased Withdrawal movement of said support, such adjustment retaining the predetermined initial setting of said limiting means undisturbed.

In testimony whereof I have hereunto affixed my signature.

STANLEY WV. BATH. 

